how to set up keychain to create generated passwords

See these articles https://support.apple.com/en-in/HT204085

https://support.apple.com/en-in/guide/mac-help/mchlp1088/10.14/mac/10.14

https://support.apple.com/en-in/guide/mac-help/mchlp2555/10.14/mac/10.14

Make sure don't use insecure passwords ( example 123 ) , in the latest version of Mac OS Mojave 10.14.6 , also clarify some thing about generated password .

http://ipadinsight.com/ipad-tips-tricks/how-to-use-icloud-keychain-to-generate-a-password-on-your-ipad/

http://osxdaily.com/2013/12/17/secure-passwords-safari-icloud-keychain-mac-os-x/

You are welcome.